Caracterización del origen del ligamento suspensorio en miembro anterior de equinos mediante ultrasonido y resonancia magnética

El objetivo del estudio fue describir la anatomía normal del origen del ligamento suspensorio del miembro anterior de equinos de trabajo, mediante el análisis de ultrasonido y resonancia magnética. Se examinaron clínicamente equinos de trabajo destinados a un frigorífico, constatando ausencia de lesiones en el ligamento suspensorio de miembros anteriores. Luego se realizó el análisis mediante ultrasonido y posteriormente a la faena se procedió al examen de resonancia magnética con las piezas cadavéricas previamente acondicionadas. Se obtuvieron imágenes transversales y longitudinales por ultrasonido. Con resonancia magnética se adquirieron imágenes longitudinal, transversal y dorsal. En ambos métodos diagnósticos se lograron medidas del diámetro dorso-palmar y latero-medial. Las imágenes en corte transversal de ultrasonido demostraron la forma rectangular del ligamento suspensorio y en imágenes longitudinales se observó el característico alineamiento fibrilar del ligamento. En cuanto a la evaluación mediante resonancia magnética, en imágenes transversales se visualizó una forma bilobulada del ligamento con una zona central oscura, y una periférica blanca debido a las intensidades de señal que adoptaron los diferentes tejidos que lo conformaron. En la imagen longitudinal se vio un aspecto de banda lisa y uniforme. En la imagen dorsal se visualizaron como líneas verticales, siendo la intensidad de la señal de intermedia a alta. La ultrasonografía y la resonancia magnética nos permitieron evaluar la constitución tisular variada que presentó el origen del ligamento suspensorio

Effective demagnetizing tensors in arrays of magnetic nanopillars

A model describing the effect of magnetic dipolar interactions on the susceptibility of magnetic nanopillars is presented. It is an extension of a recently reported model for three-dimensional randomlike dispersions of nearly spherical nanoparticles in equilibrium [Sánchez et al., Phys. Rev. B 95, 134421 (2017)2469-995010.1103/PhysRevB.95.134421], to well-ordered arrays of nanoparticles out of equilibrium. To test it, a high-quality benchmark consisting of a two-dimensional hexagonal arrangement of quasi-identical parallel nickel nanopillars embedded in a porous alumina template was fabricated. This model is based on an effective demagnetizing tensor, which only depends on a few morphological parameters of the sample, as the nearest-neighbor distance between pillars and the volume fraction of pillars in the specimen. It allows us to obtain the nanopillar intrinsic susceptibility tensor from the magnetic response of the nanopillar ensemble. The values of the in-plane and normal-to-plane susceptibility of the sample are successfully predicted by the model. Furthermore, the model reproduces the susceptibility in the applied field direction, measured for different applied field angles. In this way, it provides a simple and accurate treatment to account for the complex magnetic effects produced by dipolar interactions.Facultad de Ciencias ExactasInstituto de Física La Plat

Zinātniskā komunisma jautājumi

CNPQ - CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICOIn order to understand the magnetocaloric response of materials, it is important to analyze the interactions between the different phases present in them. Recent models have analyzed the influence of these interactions on the magnetocaloric response of composites, providing an estimate value of the interaction field that is consistent with experimental results. This paper analyzes to which extent magnetization first-order reversal curve (FORC) method can be used to calculate these interactions. It is shown that the different field ranges that are explored using these techniques (inside the hysteretic region for FORC; close to magnetic saturation for magnetocaloric effect) produce interaction field values that differ in order of magnitude, with FORC being sensitive to the lower values of the interaction field and magnetocaloric analysis accounting for the larger interactions. (C) 2015 AIP Publishing LLC.In order to understand the magnetocaloric response of materials, it is important to analyze the interactions between the different phases present in them. Recent models have analyzed the influence of these interactions on the magnetocaloric response of composites, providing an estimate value of the interaction field that is consistent with experimental results. This paper analyzes to which extent magnetization first-order reversal curve (FORC) method can be used to calculate these interactions. It is shown that the different field ranges that are explored using these techniques (inside the hysteretic region for FORCclose to magnetic saturation for magnetocaloric effect) produce interaction field values that differ in order of magnitude, with FORC being sensitive to the lower values of the interaction field and magnetocaloric analysis accounting for the larger interactions.1171714CNPQ - CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICOCNPQ - CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO401921/2013-1This work was supported by the Science Without Borders Program of the Brazilian funding agency CNPq (#401921/2013‐1), the Spanish MINECO and EU FEDER (Project No. MAT 2013-45165-P) and the PAI of the Regional Government of Andalucía (Project No. P10-FQM-6462)

Dyads of G-Quadruplex Ligands Triggering DNA Damage Response and Tumour Cell Growth Inhibition at Subnanomolar Concentration

Naphthalene diimide (NDI) dyads exhibiting a different substitution pattern and linker length have been synthesised and evaluated as G-quadruplex (G4) ligands, by investigating their cytotoxicity in selected cell lines. The dyads with the long C7 linker exhibit extremely low IC50 values, below 10\u2005nm, on different cancer cell lines. Contrary, the dyads with the shorter C4 linker were much less effective, with IC values increasing up to 1\u2005\u3bcm. Among the three dyads with the longest linker, small differences in the IC50 values emerge, suggesting that the linker length plays a more important role than the substitution pattern. We have further shown that the dyads are able to induce cellular DNA damage response, which is not limited to the telomeric regions and is likely the origin of their cytotoxicity. Both absorption titration and dynamic light scattering of the most cytotoxic dyads in the presence of hTel22 highlight their ability to induce effective G4 aggregation, acting as non-covalent cross-linking agents

Two-photon Lithography for 3D Magnetic Nanostructure Fabrication

Ferromagnetic materials have been utilised as recording media within data storage devices for many decades. Confinement of the material to a two dimensional plane is a significant bottleneck in achieving ultra-high recording densities and this has led to the proposition of three dimensional (3D) racetrack memories that utilise domain wall propagation along nanowires. However, the fabrication of 3D magnetic nanostructures of complex geometry is highly challenging and not easily achievable with standard lithography techniques. Here, by using a combination of two-photon lithography and electrochemical deposition, we show a new approach to construct 3D magnetic nanostructures of complex geometry. The magnetic properties are found to be intimately related to the 3D geometry of the structure and magnetic imaging experiments provide evidence of domain wall pinning at a 3D nanostructured junction

Interactions between heme and tau-derived R1 peptides: Binding and oxidative reactivity

The first octadecapeptide repeat fragment of tau, R1τ, in both N-terminal amine free and acetylated forms, binds with moderate affinity to both monomeric and dimeric hemin forming 1 : 1 complexes, but does not form a 2 : 1 complex. The peroxidase activity of hemin-R1τ complexes and the effect of hemin on the aggregation properties of R1τ have been also studied.</p